Gas cooking areas defined by a plate-shaped body made of glass ceramic, glass or ceramic defining the cooktop panel are available in two versions in the marketplace irrespective of whether the plate-shaped body is part of a cooktop or part of a gas range. In one of the two versions, gas radiating burners are provided below a continuous cooking area wherein the gas, which is supplied together with air, is combusted at the surface of a burner plate made of porous ceramic. In the second version, atmospheric gas burners are integrated into respective openings of the cooktop panel. These are burners having an open flame and it is this second version to which the invention relates.
These cooktop panels impose special requirements on the connection between the cooktop panel and the gas burner to be integrated therein. A rigid connection of the cooktop panel or glass plate and the gas burner or a fixedly mounted gas burner is not practical because, in the case of a blow to the gas burner, a lever force is applied to the cooktop panel defining the cooking surface. If this lever force exceeds the maximum loadability of the material of the cooktop panel, then this can lead to fracturing thereof. For this reason, cooktop apparatus of this kind impose high requirements on the construction thereof. The connection of the gas burner to the cooktop panel made of glass ceramic, glass or ceramic must be so configured that the special material characteristics of the glass ceramic, glass or ceramic are considered.
For this reason, it is necessary to mechanically decouple the cooktop panel from the cooktop apparatus and from the gas burner.
On the other hand, it must be ensured that no spillage or cleaning materials reach the interior of the gas cooktop apparatus. It is therefore necessary to provide a liquid-impenetrable connection between cooktop panel and gas burner.
A whole series of solutions for integrating the gas burner into the cooktop panel are known from the state of the art.
German Patent 4,442,572 discloses a gas cooking field having a plate-shaped body made of brittle material which can fracture. In this plate-shaped body, an opening is formed for accommodating at least one atmospheric gas burner which is held in place by a metal collar in spaced relationship to the panel. The metal collar engages the panel in the peripheral region of the opening with sealing means disposed therebetween and overlapping at both sides. The collar defines an abutment for the gas burner mounted in the clear opening of the collar.
This known integration of the gas burners in the cooktop panel ensures that no mechanically rigid connection results between the cook plate and the gas burner whereby the energy, which occurs with a mechanical load on the cook plate, can be absorbed without a fracture. Furthermore, this known connecting technique also ensures that no spillage or other liquids reach the interior space of the cooktop apparatus. However, German Patent 4,442,572 makes no further suggestions with respect to the arrangement of the gas burner itself.
U.S. Pat. No. 5,046,477 discloses an improved seal of the gas burner with respect to the glass panel in that the opening of the glass panel is only so large that it can accommodate the gas burner. To provide a seal, the gas burner is fixedly connected with its peripheral edge to the glass panel. Furthermore, the gas burner is mounted on a mounting bracket connected to the carrier frame accommodating the glass panel. A mechanically rigid connection between a form body (a panel made of glass ceramic, glass or ceramic), a carrier frame and the gas burner leads, however, to the formation of stresses in the panel when the latter is mechanically or thermally loaded. In each case, the risk of fracture of the cook plate is significantly increased thereby.
German published patent application 4,133,409 discloses a burner arrangement, such as for a cooktop, wherein at least one gas burner is mounted in a carrier frame. The peripheral surface of the gas burner is covered with a plate-shaped body made of brittle material which can fracture. Each gas burner extends through an opening in the plate-shaped body and extends above the upper surface thereof. A permanent-elastic connecting and sealing device is mounted between the form body and each gas burner. The connecting and sealing device includes a connecting and sealing element engaging fixedly and liquid tight to the peripheral region of the opening and to at least a connecting surface formed by the gas burner. The gas burner is supported by the form body and holding devices are mounted between the gas burner and the supporting frame. The holding devices become effective for each gas burner when there is a fracture of the form body and therefore a loss of its carrying capabilities. The holding devices permit a limited movement and guarantee against rotation for each of the gas burners.
This burner arrangement is very complex to assemble. Furthermore, connections held with adhesive provide a mechanically rigid connection but are disadvantageous for recycling or during assembly, for example, because of the time needed for the silicon adhesive to dry as well as for repairs during a service call. Furthermore, connections utilizing adhesives are not permanently stable with respect to temperature. The gas burners are supported by the plate-shaped form body and exhibit limited movability only with respect to the carrier frame and the housing parts. For this reason, no optimal mechanical decoupling between the gas burner and the plate-shaped form body is provided.
The state of the art described above is especially disadvantageous in that a special configuration of the burner is always necessary, for example, the sealing surface between the burner and the collar must be correspondingly configured. Also, all known solutions have the disadvantage that the cooktop must be manufactured only utilizing complex overhead assembly. This increases production costs considerably.
Because of the overhead assembly, service is very complex and requires that the apparatus be disassembled from the counter top and the disassembly of the entire apparatus insofar as this is even possible because of the use of adhesive. This time-intensive maintenance in the case of service likewise introduces very high costs.